The Bugs Bunny Show
In the original animated segments of the episode Do or Diet, Taz appears to be in "bad shape", so Bugs Bunny puts him on a carrot diet. After Stupor Duck, Taz appears to have eaten too many carrots.
Bugs Bunny's Christmas Tales
Bugs Bunny feeds Taz (dressed as Santa Claus) popcorn near the fireplace which causes his stomach to explode, ballooning him up for a second. Later on, Bugs sets up a gift exchange for Taz and when Taz goes outside to open it, it turns out to be a "Self-Inflating Rubber Life-Raft". Taz eats it without any clue and eventually balloons up, flying away into the sky.
Kraft Miracle Whip
In this promo for the Mil-Looney-Um video box sets, Granny inflates balloons with a helium tank and accidentally inflates Sylvester when he is about to catch Tweety. He is sent flying above everyone in the party, most of which are having too much fun to notice.
Taz swallows a whole air tank and suddenly inflates due to it being inside him.
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